Prime Minister Tony Blair last night warned the developed world to prepare for "pain" in its relationship with Africa to secure the "gain" of a prosperous continent.

Prime Minister Tony Blair last night warned the developed world to prepare for "pain" in its relationship with Africa to secure the "gain" of a prosperous continent.

Mr Blair, speaking on the last leg of his African tour, said the nations there, too, would have to face up to "huge challenges".

The Prime Minister's comments came after a day when he continued his latest foreign foray in sombre mood, dressed in a dark suit and black tie after he was given the news of the death of Princess Margaret.

Mr Blair first flew yesterday morning from Ghana to Sierra Leone to visit British troops there and received a spectacular traditional welcome from local tribal chiefs - as well as holding private talks with President Ahmad Tejan Kabbah.

He then travelled on to Dak- ar, capital of Senegal, to attend a seminar on the prospects for economic growth in Africa.

After that meeting, he told reporters: "There is a lot of pain in this for all sides. It's not easy for the developed world to increase its investment, to open up its markets.

"It's not easy for African countries to face huge challenges. There's pain on both sides, but the only way we can meet the pain and deal with it is if we deal with it together.

"The only way to deal with this is if there's pain all round so that there can be gain all round.

"I think there's a new spirit of willingness to work together now."

The seminar was organised by the New Partnership For African Development.

Today the Prime Minister will return to London after his four-day visit to the region, which will take his tally of foreign countries visited since September 11 to 26.